Data

Watts On Schools
B r i n g i n g S o l a r E n e r g y t o t h e C o m m u n i t i e s W e S e r v e

HOME

SCHOOLS
host sites, graphs
current weather

DATA
download data

SYSTEMS
learn how they work

ACTIVITIES
teach solar energy
invent and share

CALCULATOR
kilo-what?

LINKS
surf, search, find

SUPPORT
ask questions
get help

Watts On Schools Solar Energy Data

Downloadable Data | Uncompressing .Zip Files | Importing Data into Excel | .Dat File Descriptions | Ordinal Day of Year Calendar

DOWNLOADABLE DATA

Click the links in the table below to download raw weather and energy data from each of our systems to your computer for analysis. Complete data for previous years is available; year-to-date data for the current year is updated monthly by the fifth day of each month. You may also view, graph, compare and download performance data from these and many other solar energy systems at SolTrex.com.

	Download Data
	19	20
Link to Site	99	00	01	02	03	04	05	06
Abilene, TX	*	*	*	*	*	*	*	*
Childress, TX	*	*	*	*	*	*	*	*
Corpus Christi, TX	*	*	*	*	*	*	*	*
Del Rio, TX	*	*	*	*	*	*	*	*
El Campo, TX	*	*	*	*	*	*	*	*
Fayetteville, AR	*	*	*	*	*	*	*	*
Jefferson, TX	*	*	*	*	*	*	*	*
Laredo, TX	*	*	*	*	*	*	*	*
Longview-SH, TX	*	*	*	*	*	*	*	*
Longview-PT, TX	NA	*	*	*	*	*	*	*
Mineola, TX	*	*	*	*	*	*	*	*
Mission, TX	NA	*	*	*	*	*
Presidio, TX	*	*	*	*	*	*	*	*
Rio Hondo, TX	NA	*	*	*	*	*	*	*
San Angelo, TX	*	*	*	*	*	*	*	*
Sonora, TX	*	*	*	*	*	*	*	*
Stonewall, LA	NA	*	*	*	*	*	*	*
Texarkana, AR	*	*	*	*	*	*	*	*
Uvalde, TX	*	*	*	*	*	*	*	*

UNCOMPRESSING .ZIP FILES

The data files have been compressed using the .zip format, and will need to be uncompressed before importing them into Excel or another data processing program. To uncompress the files, you will need to load a program such as WinZip (available for free download) from http://www.pkware.com.

IMPORTING DATA INTO EXCEL

Once uncompressed, the files are stored in comma-delimted text format with a .dat extension (e.g., abilene.dat). To open the .dat file in Excel, start Excel, choose File, Import, then select the .dat file you want to import. Excel will run you through an import wizard, which will ask you to specify that the file is delimited, and then to specify the delimiter (comma). After you complete the import wizard, you will be able to save the open file in Excel format.

.DAT FILE DESCRIPTION

Data files for each site are saved in a comma-delimited format. The contents of each file look like something like this:

...
1,1,1999,252,1415,30.47,1049,.914,3.707,118.5,9.1
1,1,1999,252,1430,29.72,1030,1.343,3.659,119.4,9.14
...

Average measurements are calculated, time-stamped and recorded every fifteen minutes; thus, each line (or record) in the file represents fifteen minutes of data. "Comma-delimited" means that each column (or field) is set off from the other data by commas. The columns (fields) are defined as follows:

Field	Definition
1	Array ID. You can safely ignore this value.
2	Program version ID. This helps us keep track of how we've programmed the datalogger unit. You can ignore it, too.
3	Year (YYYY).
4	Ordinal Day of Year (1-365). See the Day of Year Calendar below or use our Excel Date Worksheet to compare and translate Ordinal dates to month and day.
5	Time of Day (0100-2400).
6	Average Temperature (degrees Celsius).
7	Average Plane of Array Solar Irradiance (watts per square meter). This is a measurement of the amount of solar energy available to the array. Under normal conditions, about 10-12 percent of this energy will be converted into electricity.
8	Average Wind Speed (meters per second).
9	Average PV System AC Power Output (kilowatts). This is the net power of the system, after the DC power has been converted to AC power by the inverter.
10	Cumulative Energy Production Meter (kWh). This field simulates an electric meter, calculating and recording the cumulative number of kilowatt-hours of electricity produced by the system.
11	System Efficiency (percent). By dividing the system's AC power output (field 9) by the amount of solar energy available to the system (FIELD 7 times the array area), we calculate and record the average system efficiency.

All averages are fifteen minute values computed from 900 observations at one second intervals. Each file is saved with a .dat extension. The file can be opened in Word or any text processing program to view the data directly, or it can be imported into Excel or most other spreadsheet programs by using the File... Import... command.

ORDINAL DAY OF YEAR CALENDAR
*Add 1 to unshaded values during leap years.

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
1	1	32	60	91	121	152	182	213	244	274	305	335
2	2	33	61	92	122	153	183	214	245	275	306	336
3	3	34	62	93	123	154	184	215	246	276	307	337
4	4	35	63	94	124	155	185	216	247	277	308	338
5	5	36	64	95	125	156	186	217	248	278	309	339
6	6	37	65	96	126	157	187	218	249	279	310	340
7	7	38	66	97	127	158	188	219	250	280	311	341
8	8	39	67	98	128	159	189	220	251	281	312	342
9	9	40	68	99	129	160	190	221	252	282	313	343
10	10	41	69	100	130	161	191	222	253	283	314	344
11	11	42	70	101	131	162	192	223	254	284	315	345
12	12	43	71	102	132	163	193	224	255	285	316	346
13	13	44	72	103	133	164	194	225	256	286	317	347
14	14	45	73	104	134	165	195	226	257	287	318	348
15	15	46	74	105	135	166	196	227	258	288	319	349
16	16	47	75	106	136	167	197	228	259	289	320	350
17	17	48	76	107	137	168	198	229	260	290	321	351
18	18	49	77	108	138	169	199	230	261	291	322	352
19	19	50	78	109	139	170	200	231	262	292	323	353
20	20	51	79	110	140	171	201	232	263	293	324	354
21	21	52	80	111	141	172	202	233	264	294	325	355
22	22	53	81	112	142	173	203	234	265	295	326	356
23	23	54	82	113	143	174	204	235	266	296	327	357
24	24	55	83	114	144	175	205	236	267	297	328	358
25	25	56	84	115	145	176	206	237	268	298	329	359
26	26	57	85	116	146	177	207	238	269	299	330	360
27	27	58	86	117	147	178	208	239	270	300	331	361
28	28	59	87	118	148	179	209	240	271	301	332	362
29	29	60	88	119	149	180	210	241	272	302	333	363
30	30		89	120	150	181	211	242	273	303	334	364
31	31		90		151		212	243		304		365

BACK | SEARCH | SPONSORS | SITE CREDITS | CONTACT US
Comments or questions about this site? Mail them to webmaster@wattsonschools.com
� Copyright 1999-2004, CSGServices, Inc. for American Electric Power